Willie Walsh, the airline's chief executive, said it had become clear that its policy would need to change in the light of widespread criticism surrounding the case of Nadia Eweida.

The airline had faced the prospect of a boycott by international travellers after an internet website was set up to co-ordinate an angry response to the suspension of Ms Eweida. A Church of England vicar went on BBC Radio 4's Today programme to urge people to shun the airline because he said it effectively discriminated against Christians.

Mr Walsh said the recent debate about the company's uniform policy had "unfairly accused British Airways of being anti-Christian".

"One of the fundamental aims of our uniform policy is to be fair and non-discriminatory," Mr Walsh said.

Related Articles

But he added: "Though our policy is consistent with that of many other airlines, it has become clear that the policy will need to change in the light of the public debate. Therefore I am initiating a review of the policy to begin immediately."

The Rev Tony Kelso, from Matchborough, West Midlands, told The Daily Telegraph: "It is ludicrous that British Airways has the Union Flag on their tail fins which is made up of sacred crosses from our United Kingdom and yet it practises this discrimination against Christians.

"They have put themselves in a massive big hole and don't know how to get out."

A spokesman for the Archbishop of York, the Rt Rev John Sentamu, hinted that he might also join the boycott.

"The Church believes that everyone deserves a second chance and that includes BA," the spokesman said. "There is a second appeal next month and, at the moment, the Archbishop believes that a boycott would be premature."

Mr Kelso said it was "a shame" that the Archbishop did not support the boycott and even more so that the Archbishop of Canterbury flew to Rome by BA to meet the Pope on Wednesday.

"From BA's point of view, they have to hope that the big Christian groups in America don't join in this boycott, but I think it is coming, they are stirring."

Meanwhile, more MPs joined a formal protest at BA's position, with Ben Bradshaw, the environment minister, saying that he would not fly on the former national carrier until it reversed its decision.

Jack Straw, the Leader of the Commons, joined his colleague Peter Hain, the Northern Ireland Secretary, in expressing his dismay at the airline's position, although he stopped short of joining the call for an embargo.

The site www.baboycott.com encourages people to destroy their British Airways frequent flyer cards, photograph the pieces and send the image to them digitally. It also offers advice on alternative flights.

Marcus Stafford, a Norfolk-based web designer who set it up, said: "This case was the last straw for me. I had just got so fed up with attacks on Englishness and Christianity that I decided to take action.

"I am not an active Christian, more a cultural one, like most people in this country, but I just thought, no more."

One contributor to the site wrote: "I usually use BA, but as a Christian, I have decided that if one person is being persecuted because of what she believes in, then BA have no need for my business. I have cut up my card."

Ann Widdecombe, the Tory MP and former Home Office minister who has been campaigning against the airline's decision, said she was delighted that the campaign had spread to the internet. "The only way to make them listen and change their minds is through the power of the pound," she said.

"Normally, parliamentary delegations travel by air and obviously we would normally prefer to travel by British Airways, but I think we should seriously consider that and say, 'No, we don't want to fly BA'."

Mr Bradshaw, who is a member of the Christian Socialist Movement, said he was taking the stance on principle. "It is a ridiculous policy to prevent someone wearing a very small crucifix," he said.

"I think what they are doing is wrong and I still hope BA will reconsider this decision. I wrote to BA when this case emerged and I wasn't satisfied with their reply.

"They explained their decision but it wasn't in a way I found convincing. I am seeking to avoid using them whenever possible."

Mr Straw said during Commons exchanges that he found the BA position "inexplicable". He said: "I strongly supported the right of women of the Muslim faith to wear the hijab — the headscarf — in all circumstances. I therefore find the ban on wearing a cross or indeed a Star of David in equivalent circumstances wholly inexplicable."

Iain Dale, the Conservative political analyst and internet "blogger", said: "The whole thing is utterly hypocritical on BA's part and I for one don't want to fly on an airline that treats people in this way.

"The adult thing to do would be to put up their hands and say 'we got it wrong', but they don't seem to want to do that."